Gourds are members of the family Cucurbitaceae (Cucurbits)
along with melons, squash and cucumbers. They're all "cucumbers" to
the botanist and "Vine Crops" to the agriculturist, and the're all fruit
but in culinary practice gourds are "vegetables".

Gourds are native to Asia and Africa and were unknown in the Americas
until brought by European traders and invaders after 1500 (some controversy
here). In any case there were already squash in the Americas that dried to
hard shells that would be called "gourds" in popular usage, but which
aren't actually gourds.

Gourds are not so neatly categorizable as squash and cucumbers, each of
which belongs to a single genus (with just a couple exceptions). Not only
are there several distinct genera of gourds but the line between
gourds and cucumbers is a bit fuzzy, and some gourds are called "melons"
even though they aren't.

For our discussion here "Gourd" will be any vine fruit belonging
to family Cucurbitaceae and native to Asia or Africa that is not
a melon or cucumber - regardless of what they're called in common usage.

This large gourd is popular in China as Winter Melon, both for its delicacy
when cooked and because with its waxy coating it can be kept well into the
winter. In India it's used for sweets and curries. Immature melon is sold
as Fuzzy Melon.

The photo specimen is a
spherical variety about 10 inches in diameter, relatively small so it can be
sold whole. The sausage shaped varieties can easily top a yard long and 50
pounds. Details and Cooking.

Bitter Melon -
[Balsam Pear, Bitter Gourd; Karela (India); Ampalaya (Philippine);
Ku gua (China), genus Momordica]
Actually a gourd, not a mellon, this is one of the most bitter of edible
vegetables, the bitterness coming from quinine or a similar anti-malarial
substance. It is reputed for many beneficial medicinal properties,
particularly treatment of diabetes, but all need further study.

Despite the bitterness this gourd is very popular throughout India, Nepal,
China and Southeast Asia and is now grown in Africa and the Caribbean. It is
not much seen in mainland Japan but is popular in Okinawa. It is a favorite
of Southeast Asian farmers here in California so the Chinese variety is
always in good supply and the Indian version is increasingly available.

The gourds are generally eaten quite green when the seed mass will be
white. As the gourd ripens fully it turns yellowish, very bitter and less
crisp. The pulpy arils surrounding the seeds become brilliant red and quite
sweet. They are popular in salads in Southeast Asia but at this point the
rest of the melon is of little use.

Chinese Bitter Melon - [Ku gua (China);
Momordica charantia}

Chinese bitter melons are less bitter than the Indian variety, and seem
to be a little less bitter in the larger sizes, such as those in the photo.
The top photo specimen was 11-3/4 inches long, 2-1/4 inches diameter and
weighed 12-5/8 ounces. As they ripen the pulpy seed surround, which is
not bitter, becomes brilliant red and quite sweet, but by time it's at
its best the melon is turning yellow and becoming mushy.
Details and Cooking

Indian Bitter Melon - [Karela (India);
Momordica charantia]

Indian bitter melons (bottom three in the photo) have a much rougher skin,
are more bitter than the Chinese variety and also come in a white
version. They are also more prone to damage and don't keep as well as the
Chinese. Miniature Indian bitter melons are popular in India and Southeast
Asia for stuffing as individual portions.
Details and Cooking

This gourd is used as a vegetable all over India and in some parts
of Southeast Asia. Usage, and rules of usage are very similar to
Karala (Indian Bitter Melon). It is commonly fried with spices and
often served with meats or fish. The specimen at the upper right is
ripe and beyond the stage where it would be cooked. This gourd
also has medicinal uses.
Photo by Sivahari distributed under license Creative
Commons
Attribution-ShareAlike v3.0 Unported.

This green is popular all over Southeast Asia, including the Philippines.
It is mildly bitter, similar to the fruit but very much less so. The photo
specimens, purchased from an Asian grower at a Los Angeles farmer's market,
were from a bundle about 32 inches long. In the lower right quarter you can
see a very immature bitter melon fruit. Flowers, if any, are small and
yellow.
Details and Cooking

Taiwan Bitter Melon -
[Momordica. charantia]

This melon is similar to the regular Chinese bitter melons but much larger
paler in color and a lot less bitter. In fact, it's hardly bitter at all.
I like them sliced, salted and eaten raw, but they seem a bit bland cooked.
Clearly this is considered a prestige vegetable because the melons were
individually shrink wrapped and carefully packed. I'm not sure they're
actually grown in Taiwan, the Asian markets around here seem to label a
lot of unusual stuff "Taiwan".
The top photo specimen was 11 inches long, 3-1/4 inches diameter and
weighed 1 pound 6-1/2 ounces.
Details and Cooking

Native to tropical Africa, fruits of this plant are about 2-3/4 inches
long and covered with soft spines, which become prickly and sharp
when the fruit dries. The leaves are a bit bitter, but cooked as a
vegetable in Gabon and Malawi. The fruit is cooked and eaten throughout
its range, and the tuberous roots are cooked and eaten in Sudan. All
parts of the plant are used midicinally.
Photo by Pharaoh han distributed under license Creative
Commons
Attribution-ShareAlike v3.0 Unported.

Despite the common English name and it's outward and inward appearance,
Gac is completely unrelated to the actual
Jackfruit.. It grows on vines like any
other gourd or cucumber and has red arils surrounding the seeds just
like a ripe Bitter Gourd should, but they
are very large. This gourd is eaten in Vietnam, combined with glutinous
rice in a dish called xôi gac. Gac is highly seasonal,
available from December into February. The photo specimen was 5-1/4 inches
diameter and weighed 2-1/2 pounds.

Gac has a higher concentration of bioavailable beta-carotene
(Vitamin A) than any other fruit or vegetable, 10 times that of carrots,
and 70 times the lycopene provided by tomatoes. It is also very high in
a number of important phytonutrients and Vitamin E, and the pulp contains
a fair amount of oils which efficiently transport these nutrients. It is
now being sold in the West in capsule form as a nutritional supplement.
Details and Cooking.

Native to southern China and northern Thailand, and closely related to
the Bitter Melons (but of genus Siraitia, not Momordica),
this rare gourd has recently become better known in the West. Extracts
from this fruit are 300 times sweeter than sugar with almost no calories.
The US FDA (Food and Drug Administration) has recently rated the fruit and
extracts from it as GRAS (Generally Recognized As Safe), so they will soon
be included as natural sweeteners in any number of products. The fruits
grow on vines and are between 2 to 2-3/4 inches diameter with sweet,
fleshy edible pulp and many seeds.
Details and Cooking.
Photo by KasugaHuang distributed under license
Creative Commons
Attribution 3.0 Unported.

This gourd comes in many shapes and sizes from long and snake like
to spherical but the form pictured is the one common in Southern
California markets. They will grow much larger but they get very bitter when
more mature. Eventually the shell hardens and the gourd becomes hollow and
may be used as a container or carved decoratively.

Young shoots and leaves are also edible. Dried strips of the gourd called
Kampyo are important in Japan and often used as edible bindings to hold other
ingredients together. Details and Cooking.

Calabash - See Bottle Gourd.
There is also a Calabash that isn't a gourd at all but the large spherical
fruit of a tree in the Bignonia family (B. Crescentia
(6 species)) native to Central and South America. Both types of calabash
are dried and used as containers.

A variety of the large to gigantic Ash Gourd that's
picked and eaten at a much earlier stage of growth. In this stage it's
covered with short bristles, thus the name, but by time I get them home
most have rubbed off. Many recipes say to peel them, but you'll have more
flavor and more melon if you just scrape them.

Asian recipes usually presume they're about 1/2 pound, but here in Los
Angeles they run from 1 pound to a shade over 2 pounds. The photo specimen
was 13 inches long and weighed 2-1/4 pounds, well above average size.
Details and Cooking.

GherkinThree fruits are called "gherkin", generally when pickled, and one of
then is a gourd.

The Tindora (Ivy Gourd) is sometimes
called Gherkin whether pickled or not.

Most well known in the U.S. as a bath sponge, these gourds are grown in
a number of varieties both for sponges and for eating. They are immensely
popular in India and also much used in Southeast Asia and China.

Grown all over Southeast Asia, these have also long been a common vegetable
here in Southern California. They are used by Asians of all stripes, from
India to the Philippines. Though commonly sold as "Chinese Okra", it is
entirely unrelated to Okra and does not resemble it in flavor, texture,
cooking properties or size, only in that it has ridges.

The skin is stiff and thin with sharp ridges running the full length.
The flesh is very delicate in both flavor and texture, yet holds its shape
well when cooked. The photo specimen was 19 inches long, 2-1/2 inches
diameter and weighed 14 ounces. They vary in shape and size. The cut one
was more uniform in diameter, 21 inches long and weighed just over 1
pound.
Details and Cooking.

Probably of African origin, these are an eating variety which may be
cylindrical or snake shaped with little or no ridging. Cylindrical ones
are generally eaten when they are about 8 to 10 inches long, snake shaped
ones depending on variety. The photo specimen in the center was 11 inches
long and 2-1/2 inches diameter.

These gourds have not yet become common in Southern California markets,
but I have found them in Indian markets in Artesia. They have a more
distinctly vegetable flavor than the Angled Luffa and store considerably
longer. In California they are grown commercially mostly for the bath
sponge produced when they mature and dry out. They are also grown in
Florida where some may be used for cooking.
Details and Cooking

Smooth Luffa - [Egyptian Luffa, Luffa
cylindrica alt L. aegyptiaca]

This is the same Luffa as the previous entry but allowed to mature
completely and dry. They are harvested for the sponge-like interior fiber
(the papery shell is easily removed). The "sponges" are popular as bath
sponges and for various household chores.

Luffas should be dried well between uses for longer life. A large one
also serves marvelously as a non-injurious club for swatting snoring bed
companions in the night. The sponge pictured is about 26 inches long.
My local market always has a pile of them for about $1.39 each but you
can pay a lot more for a short piece at an upscale bath boutique.

This Luffa is only about 5 inches long pointed at both ends with spiky
skin. It is used as a small sponge and made into massage brushes
and sponge gloves, but is more noted for medicinal uses. It has many
uses in South American folk medicine and is widely sold in the U.S. in
pill and potion form as an ingredient in sinus treatments. It also
appears in homeopathic remedies.

This tiny realative of the Snake Gourd is an important vegetable in
Bengal and Uttar Pradesh (north eastern India). They have just started
becoming available in the Indian markets here in Southern California
(spring 2013) but are still expensive at about 2013 US $5.99 per pound.
They were formerly only available canned, but availability fresh is
still very erratic.

These gourds can grow to 6 inches long but are harvested immature at
between 2 and 3 inches. The photo specimens were typically 2-1/2 inches
long and 1.2 inches diameter. The seeds are larger and more mature than
in other edible gourds and are a bit crunchy, but since these gourds are
often stuffed or sliced, the seeds are usually removed. The skin is very
thin but a little hard, so they are most often scraped. Cooked taste was
pleasant, but not really distinctive. I'd not seek these out at the
price - but then, I'm not from there.

This gourd is popular in Southern India and Southeast Asia. It comes in
various colors, sizes and shapes, growing to as long as 6 feet, and in Asia
is often seen with a rock tied to the tip to keep it growing straight. Shoots
and leaves are also eaten as a vegetable.

The flesh of this gourd is similar to the Luffa
and Bottle Gourd and like them will hold its
shape when cooked. Unlike the other two, the seed mass of the Snake Gourd is
loose and fluffy and is usually removed. Snake gourd is also used in
traditional Chinese medicine.
Details and Cooking.
Photo by Abhilash placed in public domain.

These gourds, of the same tribe as the Parval and Snake Gourds
above, but quite different in makeup, are native to the eastern
Himalayas, Yunan, China and Assam in the far northeast of India. These
vines produce fibrous fleshed fruit weighing about 4 pounds. The
more commonly used H. macrocarpa is lighter in color and lacks
the pumpkin-like sutures of H. heteroclita in the watercolor.
Each fruit has up to 8 large seeds which have a 50% fat content. They
are suspected of being slightly toxic raw, but are generally roasted
or otherwise cooked before use. Roasted, they taste like fatty pieces
of pork. In Assam these nuts are used in curries. The flesh is not
considered edible. Cooking oil can be pressed from the seeds, which is
also used medicinally, as are other parts of the plant.
Watercolor by John Fergusson 1855 copyright expired.

Native to India, this gourd is popular in the cuisines of Northern India and
Pakistan. It's becoming more common in Southern California and is seasonally
available in markets that have a significant Indian / Pakistani element in
their clientele. The gourd is eaten in an immature stage when it will be
about 3 inches in diameter and tender with skin that does not need to be
peeled. Seeds of more mature gourds are also eaten.
Details and Cooking.

A popular vegetable in India, this tiny gourd can now be found in Indian
markets in California and elsewhere. Here it is always sold green, looking
very much like a tiny cucumber, but in India it is also sometimes used in
it's scarlet red mature stage.

Tindora can be eaten raw and are a lot more crunchy than cucumbers, or they
may be cooked as a side dish or may be pickled. When pickled they are
sometimes called "gherkin" but are easy to tell from the real
Gherkin and from cucumber gherkins by
their smooth skin. Typically they are between 2-1/2 and 3-1/4 inches long,
3/4 to 7/8 inch diameter and weigh around 5/8 ounce.
Details and Cooking.